// 09

interface Radio {
	switchRadio(trigger: boolean): void
}
interface Battery {
	checkBatteryStatus(): void
}
interface RadioWithBattery extends Radio {
	checkBatteryStatus(): void
}

class Car implements Radio {
	switchRadio(trigger: boolean) {}
}

class Cellphone implements RadioWithBattery {
	switchRadio(trigger: boolean) {}
	checkBatteryStatus() {}
}
